The St Botolph Building by Grimshaw Architects is a new-build office building located in the heart of the City of London. We were commissioned to design the lighting for the internal public spaces, and to create an identity for the building exterior.

On entering the vast reception, building users experience the sensation of light used as if it were a building material. The entire space appears to be wrapped in light, with the walls and balustrades exhibiting a fabric-like appearance that both defines the space and expresses the changes in level.

The effect is achieved by a unique bespoke cladding system into which the lighting has been integrated. This system, developed in close collaboration with the architects, both lightens the deep plan space by day, and creates a strong impact after dark as the downlighting is progressively switched down.

The spine of the building is formed by a complex lift system. We encouraged the use of glass floors to lighten this huge structure, and enhanced this through uplighting, creating a dramatic entrance at each office level.

The exterior of the building is simply accentuated through backlighting of the roof louvres and reinforcement of the stair cores. An innovative control methodology within the stair cores enables energy-saving; background light levels are raised only when the stairs are used, and even then only on the appropriate parts of the stair. The apparent movement of light as people ascend or descend helps to animate the facades.

Restrained use of blue light - echoing the colour of the building - highlights the exposed boiler flues on the prominent southern façade, helping the building to retain its identity in the cityscape after dark.